I was impressed with Great Northern right from the start. Alana came do assess my attic. She explained the work that would be done and answered all my questions. Derek and John were here yesterday to do the job. They used my bedroom window to access my attic, covering the carpet to protect it from soiling. They did a great job cleaning up afterward. They were also happy to let me have a look at the work after installing the vents, then after the insulation had been installed. I would highly recommend Great Northern.